Fluid shortening is useful in the preparation of baked goods and bread-making processes. The function of fluid shortenings is similar to plastic shortenings in baking processes, but fluid shortenings are much preferred for use in commercial baking processes due to ease in handling, pumping, and metering. Fluid shortenings characteristically are fluid at temperatures of about 60.degree. F. to 100.degree. F. and should not become unstable in storage over this temperature range, or in use, by separation into two distinct liquid phases or liquid-solid phases; i.e., producing a supernatent liquid phase and a precipitate phase. Fluid shortenings should possess a stabilized fluid consistency wherein the viscosity remains relatively consistent over a wide temperature range.
Fluid shortenings or fat compositions are known in the art containing hard mono- and diglyceride emulsifiers having an iodine value of less than 15 and usually about 0 to 5. Problems have occurred in conventional prior art fluid shortenings, however, wherein the fluid shortenings have a tendency to firm or solidify upon encountering temperatures below about 50.degree. F. Other suggested conventional fluid shortenings containing stable suspensions of about 5 to 7 percent finely divided saturated solid fatty acid hard glycerides lack sufficient solid fat for use in a continuous-mix bread-making process in addition to lacking a stability in excess of about 30 days. Still other prior art fluid shortenings are based on solid hydrogenated hard fats to overcome oxidation instability but unfortunately are of high viscosity and become unmanageable with varying winter and summer temperatures.
It should be understood the term "fluid" for purposes of the present application is not necessarily synonomous with liquid. A fluid shortening normally is considered to have both liquid and solid phases, the latter being in the form of solid particles of fat and emulsifier in suspension. The term liquid implies no solid phase.
Prior U.S. Pat. No. 3,914,452, to Max E. Norris, assigned to assignee of the present application, discloses an improved fluid shortening which contains about 4 to 14 weight parts of a soft mono- and diglyceride, having an iodine value of more than about 40, in combination with about 2 to 8 weight parts of an ester emulsifier, 0 to 8 weight parts of a solid stearine, and at least about 40 weight parts of liquid vegetable oil. The fluid shortening is a stabilized dispersion in vegetable oil, and is produced by melting a blend of the components at temperatures sufficient to force a melt, subjecting the melt to rapid chilling in a scraped-wall chiller such as a Votator "A" unit, and then agitation in Votator "B" unit, followed by prolonged agitation or fluidization in a tank referred to as a stehling tank, the chilling, votation and stehling being carried out to and at a temperature in the range of about 80.degree. F. to 90.degree. F. The purpose of the chilling, votation and stehling is to develop a beta-crystal polymorphic form of the solidified ingredients necessary to obtain a suspension which is both fluid and stable. The fluid shortening of this patent had the advantage, among others, that it possessed a stabilized fluid consistency the viscosity of which remained relatively constant over a wide temperature range.
In copending application Ser. No. 747,296, there is claimed the improvement of a unique emulisifier blend which is capable of being mixed with a vegetable oil to produce a fluid shortening. The uniqueness of the blend is such that it can be admixed with the vegetable oil by simple mechanical mixing without the necessity of the stehling steps of prior U.S. Pat. No. 3,914,452, and still produce a stable product. The advatage of the invention of Ser. No. 747,296 is that, in certain instances, it may be desirable to save on shipping costs by shipping only the emulsifier components and other shortening ingredients absent the vegetable oil to a point of further processing. Such point of further processing may not possess the stehling equipment and capability necessary to permit the manufacture of the shortening in accordance with the procedure of the '452 patent. The essential aspect of the invention of the copending application resided in a concentrate blend consisting essentially of a liquid partial glycerol ester food emulsifier vehicle having dispersed therein an ethoxylated fatty acid ester and a solid beta-phase fine crystalline food emulsifier component, the proportions of ingredients being such as to produce a fluent cloudy suspension. Preferred solid beta-phase crystalline food emulsifers were an alkali or alkaline earth metal salt of an acyl lactylate; and a succinylated mono- and diglyceride. It was found that the unique combination of emulsifier ingredients rendered the blend not only readily mixable with a vegetable oil, but also stable in the vegetable oil to produce a shortening capable of being stored for long periods of time.
Another advantage of the concentrate of the copending application was that it gave a shortening product having distinctly improved functionalities over conventional fluid shortenings.
The present invention constitutes a still further advance in the manufacture of shortenings, employing the technology in part of prior application Ser. No. 747,296.